The researchers at the CEMALB have also examined various response features of 27 individuals (13 healthy, 4 allergic non asthmatics, 10 allergic asthmatics) defined as being responsive (R, n=18) or non-responsive (NR, n=9) to O3 based on airway PMN influx (%PMNs). Among the factors explored were inflammatory responses, baseline characteristics and gene expression profiles in recovered sputum cells. The researchers have also observed that within individuals, PMN response to O3 and LPS correlate, and anticipate that WSP will induce inflammatory responses via mechanisms similar to those for these pollutants.